The Association Between Serum Riboflavin and Flavin Mononucleotide With Pancreatic Cancer: Findings From a Prospective Cohort Study.

OBJECTIVES: Vitamin B2 (riboflavin) has a prime role in metabolic reactions imperative to cell cycle and proliferation. We investigated the associations between serum concentrations of riboflavin flavin mononucleotide with the risk of pancreatic cancer in a nested case-control study involving 58 cases and 104 matched controls. METHODS: The Singapore Chinese Health Study, an ongoing prospective cohort study of 63,257 Chinese Singaporeans. Conditional logistic regression method was used to evaluate these associations with adjustment for potential confounders including the level of education, body mass index, smoking status, alcohol consumption, history of diabetes, serum cotinine and pyridoxal 5'-phosphate, estimated glomerular filtration rate, and total methyl donors (ie, the sum of serum choline, betaine, and methionine). RESULTS: The risk of pancreatic cancer increased with increasing level of serum riboflavin in a dose-dependent manner, especially in men (Ptrend = 0.003). The odds ratio (95% confidence intervals) of pancreatic cancer for the second and third tertiles of serum riboflavin, compared with the lowest tertile, were 9.92 (1.65-59.77) and 25.59 (3.09-212.00), respectively. This positive association was stronger in individuals with a longer follow-up period (≥7 years). CONCLUSIONS: The findings suggest a potential role of riboflavin in the development of pancreatic cancer, especially in men.

Association Between Serum Vitamins and the Risk of Alzheimer's Disease in Chinese Population.

BACKGROUND: Alzheimer's disease (AD) is a chronic and fatal neurodegenerative disease; accumulating evidence suggests that vitamin deficiency is associated with the risk of AD. However, studies attempting to elucidate the relationship between vitamins and AD varied widely. OBJECTIVE: This study aimed to investigate the relationship between serum vitamin levels and AD in a cohort of the Chinese population. METHODS: A total of 368 AD patients and 574 healthy controls were recruited in this study; serum vitamin A, B1, B6, B9, B12, C, D, and E were measured in all participants. RESULTS: Compared with the controls, vitamin B2, B9, B12, D, and E were significantly reduced in AD patients. Lower levels of vitamin B2, B9, B12, D, and E were associated with the risk of AD. After adjusting for age and gender, low levels of vitamin B2, B9, and B12 were still related to the risk of AD. In addition, a negative correlation was determined between vitamin E concentration and Activity of Daily Living Scale score while no significant association was found between serum vitamins and age at onset, disease duration, Mini-Mental State Examination, and Neuropsychiatric Inventory Questionnaire score. CONCLUSION: We conclude that lower vitamin B2, B9, B12, D, and E might be associated with the risk of AD, especially vitamin B2, B9, and B12. And lower vitamin E might be related to severe ability impairment of daily activities.

The Effect of a Single Bout of Exercise on Vitamin B2 Status Is Not Different between High- and Low-Fit Females.

High-fitness individuals have been suggested to be at risk of a poor vitamin B2 (riboflavin) status due to a potentially higher vitamin B2 demand, as measured by the erythrocyte glutathione reductase (EGR) activation coefficient (EGRAC). Longer-term exercise interventions have been shown to result in a lower vitamin B2 status, but studies are contradictory. Short-term exercise effects potentially contribute to discrepancies between studies but have only been tested in limited study populations. This study investigated if vitamin B2 status, measured by EGRAC, is affected by a single exercise bout in females who differ in fitness levels, and that represents long-term physical activity. At baseline and overnight after a 60-min cycling bout at 70% V·O2peak, EGR activity and EGRAC were measured in 31 young female adults, divided into a high-fit (V·O2peak ≥ 47 mL/kg/min, N = 15) and low-fit (V·O2peak ≤ 37 mL/kg/min, N = 16) group. A single exercise bout significantly increased EGR activity in high-fit and low-fit females (Ptime = 0.006). This response was not affected by fitness level (Ptime*group = 0.256). The effect of exercise on EGRAC was not significant (Ptime = 0.079) and not influenced by EGR activity. The exercise response of EGRAC was not significantly different between high-fit and low-fit females (Ptime*group = 0.141). Thus, a single exercise bout increased EGR activity, but did not affect EGRAC, indicating that vitamin B2 status was not affected. The exercise response on EGRAC and EGR did not differ between high-fit and low-fit females.

Kynurenine pathway activation and deviation to anthranilic and kynurenic acid in fibrosing chronic graft-versus-host disease.

Fibrosing chronic graft-versus-host disease (cGVHD) is a debilitating complication of allogeneic stem cell transplantation (alloSCT). A driver of fibrosis is the kynurenine (Kyn) pathway, and Kyn metabolism patterns and cytokines may influence cGVHD severity and manifestation (fibrosing versus gastrointestinal [GI] cGVHD). Using a liquid chromatography-tandem mass spectrometry approach on sera obtained from 425 patients with allografts, we identified high CXCL9, high indoleamine-2,3-dioxygenase (IDO) activity, and an activated Kyn pathway as common characteristics in all cGVHD subtypes. Specific Kyn metabolism patterns could be identified for non-severe cGVHD, severe GI cGVHD, and fibrosing cGVHD, respectively. Specifically, fibrosing cGVHD was associated with a distinct pathway shift toward anthranilic and kynurenic acid, correlating with reduced activity of the vitamin-B2-dependent kynurenine monooxygenase, low vitamin B6, and increased interleukin-18. The Kyn metabolite signature is a candidate biomarker for severe fibrosing cGVHD and provides a rationale for translational trials on prophylactic vitamin B2/B6 supplementation for cGVHD prevention.

Micronutrient supplementation of lactating Guatemalan women acutely increases infants' intake of riboflavin, thiamin, pyridoxal, and cobalamin, but not niacin, in a randomized crossover trial.

BACKGROUND: Maternal supplementation during lactation could increase milk B-vitamin concentrations, but little is known about the kinetics of milk vitamin responses. OBJECTIVES: We compared acute effects of maternal lipid-based nutrient supplement (LNS) consumption (n = 22 nutrients, 175%-212% of the RDA intake for the nutrients examined), as a single dose or at spaced intervals during 8 h, on milk concentrations and infant intake from milk of B-vitamins. METHODS: This randomized crossover trial in Quetzaltenango, Guatemala included 26 mother-infant dyads 4-6 mo postpartum who were randomly assigned to receive 3 treatments in a random order: bolus 30-g dose of LNS (Bolus); 3 × 10-g doses of LNS (Divided); and no LNS (Control), with control meals. Mothers attended three 8-h visits during which infant milk consumption was measured and milk samples were collected at every feed. Infant intake was assessed as $\mathop \sum \nolimits_{i\ = \ 1}^n ( {{\rm{milk\ volum}}{{\rm{e}}_{{\rm{feed\ }}n}} \times \ {\rm{nutrient\ concentratio}}{{\rm{n}}_{{\rm{feed}}\ n}}} )$ over 8 h. RESULTS: Maternal supplementation with the Bolus or Divided dose increased least-squares mean (95% CI) milk and infant intakes of riboflavin [milk: Bolus: 154.4 (138.2, 172.5) µg · min-1 · mL-1; Control: 84.5 (75.8, 94.3) µg · min-1 · mL-1; infant: Bolus: 64.5 (56.1, 74.3) µg; Control: 34.5 (30.0, 39.6) µg], thiamin [milk: Bolus: 10.9 (10.1, 11.7) µg · min-1 · mL-1; Control: 7.7 (7.2, 8.3) µg · min-1 · mL-1; infant: Bolus: 5.1 (4.4, 6.0) µg; Control: 3.4 (2.9, 4.0) µg], and pyridoxal [milk: Bolus: 90.5 (82.8, 98.9) µg · min-1 · mL-1; Control: 60.8 (55.8, 66.3) µg · min-1 · mL-1; infant: Bolus: 39.4 (33.5, 46.4) µg; Control: 25.0 (21.4, 29.2) µg] (all P < 0.001). Only the Bolus dose increased cobalamin in milk [Bolus: 0.054 (0.047, 0.061) µg · min-1 · mL-1; Control: 0.041 (0.035, 0.048) µg · min-1 · mL-1, P = 0.039] and infant cobalamin intake [Bolus: 0.023 (0.020, 0.027) µg; Control: 0.015 (0.013, 0.018) µg, P = 0.001] compared with Control. Niacin was unaffected. CONCLUSIONS: Maternal supplementation with LNS as a Bolus or Divided dose was similarly effective at increasing milk riboflavin, thiamin, and pyridoxal and infant intakes, whereas only the Bolus dose increased cobalamin. Niacin was unaffected in 8 h. This trial was registered at clinicaltrials.gov as NCT02464111.

DNA damage is inversely associated to blood levels of DHA and EPA fatty acids in Brazilian children and adolescents.

This study aimed to investigate the association between DNA damage and blood levels of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), retinol, beta-carotene and riboflavin in Brazilian children and adolescents. Subjects (n = 140) were healthy boys and girls aged 9 to 13 years in Ribeirão Preto (SP, Brazil). Data collection included anthropometry, assessment of energy intake and blood sampling. DNA damage was evaluated by single-cell gel electrophoresis (comet assay). Principal component analysis (PCA) was used to verify associations between blood concentrations of vitamins, polyunsaturated fatty acids and DNA damage. Multiple regression analyses, k-means cluster, and analysis of covariance (ANCOVA), adjusted for confounding variables such as age, sex, energy intake, body mass index and total cholesterol (when needed), were applied to confirm the associations. PCA explained 69.4% of the inverse relationships between DNA damage and blood levels of DHA, EPA, retinol, and beta-carotene. Results were confirmed by ANCOVA and multiple regression analyses for DHA and EPA. In conclusion, omega-3-fatty acids were inversely associated with DNA damage in Brazilian children and adolescents and may be a protective factor against the development of future diseases.

The Homozygous Hemoglobin EE Variant Is Associated with Poorer Riboflavin Status in Cambodian Women of Reproductive Age.

BACKGROUND: Riboflavin is required for erythropoiesis, which is increased in people with hemoglobinopathies due to increased hemolysis and erythrocyte turnover. Dietary intake and status of riboflavin is poor in Cambodia, where hemoglobinopathies are common. OBJECTIVE: We assessed the association between genetic hemoglobin disorders and riboflavin status in women of reproductive age in Cambodia. METHODS: Venous blood samples from 515 Cambodian women of reproductive age, 18-45 y, were analyzed for biomarker status of riboflavin [erythrocyte glutathione reductase activation coefficient (EGRac)], genetic hemoglobin (Hb) disorders, and hematological indices. Linear regression analysis was used to estimate the association between EGRac with Hb, ferritin, and Hb genotypes. EGRac was log transformed in the analyses, and the regression coefficients represent the geometric mean differences. RESULTS: Genetic Hb disorders were present in 57% of the population, with the homozygous hemoglobin E variant (Hb EE) occurring in ∼10% of women (n = 53). Deficient (EGRac ≥1.40) or marginal riboflavin status (EGRac ≥1.30 and <1.40) was observed in 92% (n = 475) of women. The variant Hb EE genotype was associated with 18% (95% CI: 9%, 28%) higher geometric mean EGRac values than the normal Hb AA genotype (P < 0.001). CONCLUSIONS: Although riboflavin biomarker deficiency or marginal status is widely prevalent in Cambodian women, lower riboflavin status was observed more frequently in women with the Hb EE genotype than in women with normal Hb AA. The relation between genetic Hb disorders and riboflavin warrants further investigation. This trial was registered at clinicaltrials.gov as NCT01593423 and NCT02481375.

Circulating trimethyllysine and risk of acute myocardial infarction in patients with suspected stable coronary heart disease.

BACKGROUND: The carnitine precursor trimethyllysine (TML) is associated with progression of atherosclerosis, possibly through a relationship with trimethylamine-N-oxide (TMAO). Riboflavin is a cofactor in TMAO synthesis. We examined prospective relationships of circulating TML and TMAO with acute myocardial infarction (AMI) and potential effect modifications by riboflavin status. METHODS: By Cox modelling, risk associations were examined amongst 4098 patients (71.8% men) with suspected stable angina pectoris. Subgroup analyses were performed according to median plasma riboflavin. RESULTS: During a median follow-up of 4.9 years, 336 (8.2%) patients experienced an AMI. The age- and sex-adjusted hazard ratio (HR) (95% CI) comparing the 4th vs. 1st TML quartile was 2.19 (1.56-3.09). Multivariable adjustment for traditional cardiovascular risk factors and indices of renal function only slightly attenuated the risk estimates [HR (95% CI) 1.79 (1.23-2.59)], which were particularly strong amongst patients with riboflavin levels above the median (Pint  = 0.035). Plasma TML and TMAO were strongly correlated (rs  = 0.41; P < 0.001); however, plasma TMAO was not associated with AMI risk in adjusted analyses [HR (95% CI) 0.81 (0.58-1.14)]. No interaction between TML and TMAO was observed. CONCLUSION: Amongst patients with suspected stable angina pectoris, plasma TML, but not TMAO, independently predicted risk of AMI. Our results motivate further research on metabolic processes determining TML levels and their potential associations with cardiovascular disease. We did not adjust for multiple comparisons, and the subgroup analyses should be interpreted with caution.

Vitamin B2 and Folate Concentrations are Associated with ARA, EPA and DHA Fatty Acids in Red Blood Cells of Brazilian Children and Adolescents.

Vitamins B2, B6, B12, and folate are essential for methylation reactions and possibly influence the transport of polyunsaturated fatty acids in plasma and red blood cells (RBC). Associations between B-vitamin biomarkers and fatty acid (FA) profile were analyzed in Brazilian children and adolescents. This cross-sectional study included 249 children and adolescents, aged 9-13 years old. Dietary intake was assessed by the food frequency questionnaire and the healthy eating index (HEI). Biomarkers for vitamins B2, B6, B12, and folate were measured in plasma. The FA profile and the metabolites of one-carbon metabolism were measured in RBC. Associations were tested with multiple linear regression models. An increase of 1 nmol/L in vitamin B2 was associated with an increase of 0.19 mg/dL of EPA, 0.20 mg/dL of ARA, and 0.25 mg/dL of DHA in RBC. An increase of 1 ng/mL in plasma folate was associated with an increase of 0.14 mg/dL of EPA, 0.22 mg/dL of ARA, and 0.21 mg/dL of DHA in RBC. These findings highlight the importance of an adequate intake of vitamin B2 and folate in childhood, since they may improve the FA profile in RBCs and may help prevent cardiovascular disease.

[The association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma].

Objective: To investigate the association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma (ESCC) in China. Methods: From March 2014 to September 2018, ESCC patients from three hospitals (the Affiliated Hospital of Medical College of Shantou University, Shantou Central Hospital in Southern Chaoshan area and First Affiliated Hospital of Zhengzhou University in Northern Taihang Mountain) were selected as a case group; non-esophageal patients who had a physical examination were selected as a control group. The case and control group were paired by age (±5 years) and a 1:1 ration. A total of 1 528 subjects were enrolled including 764 patients in the case group and 764 patients in the control group. About 3-5 ml venous blood samples were collected, and the erythrocyte glutathione reductase activity coefficient (GRAC) was measured to assess the whole blood riboflavin level. A multivariate conditional logistic regression model was used to analyze the association between the GRAC and the risk of ESCC. The association between the GRAC and the prognosis of ESCC was analyzed by using Cox proportional risk regression model based on 288 patients with complete survival data. They were divided into two groups, the high GRAC group (GRAC≥7.87) group and the low GRAC group (GRAC<7.87) according to the strongest correlation between the total survival time, survival outcome and GRAC (GRAC=7.87). Results: Among the 1 528 patients, 958 patients were from Southern Chaoshan area, including 479 patients in the case group with an average age about (59.90±9.34) years and 479 patients in the control group with an average age about (59.55±8.77) years. Other 570 patients were from Northern Taihang Mountain area, including 285 patients in the case group with an average age (58.39±5.19) years and 285 patients in the control group with an average age about (58.74±4.57) years. The multivariate conditional logistic regression showed that the OR (95%CI) of the GRAC and the risk of ESCC was 1.009 (0.998-1.019). The Cox proportional hazard regression model analysis showed that the HR (95%CI) of the high GRAC group was 1.712 (1.034-2.824) compared with the low GRAC group in the 50-70 years group. Conclusion: The whole blood riboflavin level might not be associated with the occurrence of ESCC. The high whole blood riboflavin level would be more beneficial to the prognosis of ESCC patients aged 50-70 years.

[Magnesium and vitamin B2 status of children with bronchial asthma and obesity].

Insufficiency or deficiency of some micronutrients may be additional modifying factors that influence the pathogenesis of the disease and the effectiveness of standard pharmacotherapy. The aim of the study - to evaluate the level of magnesium and vitamin B2 in blood serum of patients with bronchial asthma and obesity in order to develop methods for individual correction of deficiency. Material and methods. The study included 51 children aged 12-17 years. The first group included 23 patients (12 girls and 11 boys) with asthma with comorbidities (obesity), and the second group consisted of 28 children (10 girls and 18 boys) with obesity. The concentration of magnesium in blood serum was determined by a colorimetric method without deproteinization, and vitamin B2 - by an immunological microbiological method. Results and discussion. When analyzing the concentration of magnesium in blood serum of the examined children, it was found that in patients with bronchial asthma and obesity, a reduced content of this mineral was observed in 15 (65.2%) patients. The average magnesium concentration was 0.66±0.02 mmol/l at a rate of 0.7-1.2 mmol/l. A statistically significant decrease in the magnesium level in children suffering from asthma and obesity was noted, compared with the level in children with obesity (0.66 [0.57; 0.73] vs 0.71 [0.67; 0.73] mmol/l, р<0.05). Low serum magnesium levels in obese patients were detected more rarely (р<0.05) - only in 6 (21.4%) children, mostly in patients with grade III obesity. The remaining 22 (78.6%) children had magnesium level within the normal range. Patients with low serum magnesium levels showed increased irritability, sleep disturbance, loss of memory and concentration. Vitamin B2 levels in all examined children were within the normal range (137-370 ng/ml). Conclusion. The results indicate a decrease in the concentration of magnesium and normal levels of vitamin B2 in serum in patients with bronchial asthma and obesity. Low serum magnesium levels were observed in children with low bronchial asthma control. To increase the effectiveness of therapy and control the symptoms of bronchial asthma, especially when combined with obesity, correction of the accompanying magnesium deficiency is necessary.

Suboptimal Biochemical Riboflavin Status Is Associated with Lower Hemoglobin and Higher Rates of Anemia in a Sample of Canadian and Malaysian Women of Reproductive Age.

BACKGROUND: Riboflavin is required for several redox reactions. Clinical riboflavin deficiency occurs mainly in low-income countries, where it is associated with anemia. The functional significance of suboptimal riboflavin status in different populations and its role in anemia is not well understood. OBJECTIVES: We assessed the biomarker status of riboflavin and its association with hemoglobin concentration and anemia in women living in Vancouver, Canada, and Kuala Lumpur, Malaysia. METHODS: Healthy nonpregnant, nonbreastfeeding women (19-45 y) were recruited from Canada ( n = 206) and Malaysia (n = 210) via convenience sampling. Fasting blood was collected to assess riboflavin status [erythrocyte glutathione reductase activity coefficient (EGRac)], hematological indicators, soluble transferrin receptor (sTfR), ferritin, vitamin A, folate, and vitamin B-12 concentrations. Linear and logistic regression models were used to assess the association of riboflavin status with hemoglobin concentration and anemia. RESULTS: EGRac (mean ± SD) values were higher, indicating poorer riboflavin status, in Malaysian compared with Canadian women (1.49 ± 0.17 compared with 1.38 ± 0.11). Likewise, riboflavin biomarker deficiency (EGRac ≥1.40) was significantly more prevalent among Malaysians than Canadians (71% compared with 40%). More Malaysian than Canadian women were anemic (hemoglobin <120 g/L; 18% compared with 7%). With use of linear regression (pooled sample; n = 416), EGRac values were negatively associated with hemoglobin concentration (r = -0.18; P < 0.001). This relation remained significant (P = 0.029) after adjusting for age, parity, ethnicity, vitamin B-12, folate, sTfR, ferritin, and vitamin A. Women with riboflavin deficiency (EGRac ≥1.40) were twice as likely to present with anemia (adjusted OR: 2.38; 95% CI: 1.08, 5.27) compared with women with EGRac <1.40. CONCLUSIONS: Biochemical riboflavin deficiency was observed in Canadian and Malaysian women, with higher rates of deficiency among Malaysian women. Deficient biomarker status of riboflavin was a weak but significant predictor of hemoglobin and anemia, suggesting that the correction of riboflavin deficiency may potentially play a small protective role in anemia, but this requires further investigation.

Association between Postpartum Nutritional Status and Postpartum Depression Symptoms.

Taiwanese women may practice traditional confinement after childbirth, and no study has investigated the nutritional status and the effects of postpartum depression on such women. The aim of this study was to investigate the association between nutritional status and postpartum depression at 6-8 weeks postpartum. A cross-sectional study was conducted on postpartum women who returned to the obstetrics and gynecology clinic for routine examination from January 2016 to September 2017. A total of 344 women received assessments based on the Edinburgh Postnatal Depression Scale (EPDS). An EPDS score of ≥10 indicated the presence of postpartum depressive symptoms (PPDS). A total of 97 women without such symptoms and 23 with PPDS completed nutritional parameter analyses and questionnaires. The results showed that the prevalence of postpartum depression (PPD) was 8.4%. The proportion was 70% for those who practiced confinement at home, significantly higher than for those in the non-PPDS group (45%). The overall psychological stress score was significantly higher and the postpartum care satisfaction score was significantly lower in those with PPDS compared to those without. In terms of nutritional biomarkers, the plasma riboflavin levels in the PPDS group were significantly lower than those in their symptomless counterparts (13.9%). The vitamin D insufficiency and deficiency rates in the non-PPD and PPDS groups were 35%, 41%, 48%, 26%, respectively. However, compared with those in the non-PPDS group, those with PPDS had significantly higher ratios of Σn-6/Σn-3, C20:3n-6/C18:3n-6, and C20:4n-6/(C20:5n-3 + C22:6n-3) (by 8.2%, 79.7%, and 8.8%, respectively), whereas they had lower ratios of C22:6n-3/C22:5n-6 (by 15.5%). Higher plasma riboflavin and erythrocyte C16:1n-9, C24:1n-9, C18:3n-6, and C20:5n-3 levels and lower Σn-6 fatty acid and C22:5n-6 levels decreased the risk of PPD after type of confinement, overall mental stress scores, and postpartum care satisfaction scores were adjusted for the logistic regression analysis. In conclusion, the plasma riboflavin level and erythrocyte fatty acid composition are potentially major contributors to PPD development.

Serum levels of single-carbon metabolism vitamins and homocysteine in head-and-neck squamous cell carcinoma: Preliminary report.

Background: Head-and-neck carcinomas are a heterogeneous group of malignancies arising from the upper aerodigestive tract. Tobacco and alcohol are the leading etiological factors; however, bioactive food components, including those that modulate DNA methylation, are being linked to susceptibility. This work assesses the distribution of head-and-neck cancers presenting at a tertiary health institution and determined the serum level of the vitamins and an amino acid involved in the methionine cycle, in view of increasing acceptance of the significant role of DNA methylation in the pathogenesis of cancers. Patients and Methods: This study involved 30 newly diagnosed cases of head-and-neck squamous cell carcinoma. Thirty apparently healthy volunteers served as controls. The test cases were made up of 19 males and 11 females while controls were made up of 14 males and 16 females. The median ages of the test cases and controls were 59 and 63 years, respectively. Sera obtained from participants' blood were analyzed by high-performance liquid chromatography technique. The study protocol was approved by the joint University of Ibadan/University College Hospital Institution Review Board. Results: There is a male dominance in the number of cases at male-to-female ratio of 1.7: 1. The oral cavity was the most-affected site. Serum levels of Vitamin B2, B6, B12, and homocysteine were lower in cases compared with controls but not significantly so. However, serum Vitamin A and folic acid levels were significantly lower among the cases ([0.62 vs. 0.71, z = -2.50, P = 0.02], [26.05 vs. 30.82, z = 0.20, P = 0.00]) compared with controls. Only tobacco and alcohol use showed a significant association with head-and-neck cancer, but not family history of cancer or alcohol use alone (P = 0.00). Conclusion: Significantly low serum Vitamin A and hypofolataemia are associated with head-and-neck squamous cell carcinoma. This is suggestive of a role for these vitamins in the etiopathogenesis of the disease.

RésuméContexte: Les carcinomes de la tête et du cou sont un groupe hétérogène de tumeurs malignes provenant du tractus aérodigestif supérieur. Le tabac et l'alcool sont les principaux facteurs étiologiques ; cependant, les composants alimentaires bioactifs, y compris ceux qui modulent la méthylation de l'ADN, sont liés à la susceptibilité. Ce travail évalue la répartition des cancers de la tête et du cou présentant a une institution de santé tertiaire et a déterminé le niveau sérique des vitamines et un aminoacide impliqués dans le cycle de la méthionine, au vu de la croissante acceptation et du rôle signifiant la méthylation de l'ADN dans la pathogenèse des cancers. Patients et méthodes: Cette étude portait sur 30 cas nouvellement diagnostiqués de carcinome épidermoïde de la tête et du cou. Trente volontaires apparemment en bonne santé ont servi de contrôles. Les sujets testés étaient composés de 19 hommes et de 11 femmes, tandis que les témoins étaient composés de 14 hommes et de 16 femmes. L'âge médian des cas tests et des témoins était de 59 et 63 ans, respectivement. Les sérums obtenus à partir du sang des participants ont été analysés par la technique de chromatographie liquide à haute performance. L'étude a été approuvée par le comité mixte de revue des institutions de l'Université d'Ibadan/Collège Hospitalier Universitaire. Résultats: Il y a une dominance masculine dans le nombre de cas avec un ratio homme-femme de 1,7 : 1. La cavité orale était le site le plus touché. Les taux sériques de vitamine B2, B6, B12et d'homocystéine étaient plus bas parmi les cas par rapport aux témoins mais pas de manière significative. Néanmoins, les niveaux sériques de vitamine A et d'acide folique étaient plus bas parmi les cas ([0,62 vs 0,71 ; z = -2.02 ; P = 0,02], [26,5 vs 30,82 ; z = 0,20 ; P = 0,00]) par rapport aux témoins. Seule l'usage du tabac et d'alcool a montré une association significative avec le cancer de la tête et du cou, mais pas les antécédents familiaux de cancer ou la consommation d'alcool seul (P = 0,00). Conclusion: Les niveaux sériques significativement bas de vitamine A et d'hypovolémie sont associés au carcinome épidermoïde de la tête et du cou. Ceci suggère un rôle pour ces vitamines dans l'étiopathogenèse de la maladie.

A novel LC-MS/MS assay for vitamin B1, B2 and B6 determination in dried blood spots and its application in children.

Thiamin, riboflavin and pyridoxal phosphate (PLP) concentrations are useful indices for evaluating vitamin B1, B2 and B6 status. Several HPLC assays have been developed for determining thiamin, riboflavin and PLP in biological matrix. However, no existing LC-MS/MS methods can be used to quantify thiamin, riboflavin and PLP in dried blood spots (DBSs), which are often used as a sampling/storage vessel for blood from infants and children. This study evaluated the validity, reliability and stability of an LC-MS/MS assay for measuring thiamin, riboflavin and PLP in DBS cards. DBS samples were deproteinized by adding trichloroacetic acid containing thiamine-[13C4], riboflavin-[13C4,15N2] and pyridoxal-d3 as internal standards. Thiamin, riboflavin and PLP were separated on a C8 column with a 5-min run time. Both the between-run and within-run variable coefficients (CV% values) were < 8.56%. The accuracies were good and showed relative errors (RE% values) from -7.40% to 3.12%. The lower limits of quantification (LLOQs) ranged from 0.2 to 0.5 ng/mL, and the recoveries were from 81.49% to 112.23% for all 3 analytes. The matrix effects (ME% values) were acceptable, and the CV% values of the internal standard-normalized matrix factors were <15% (n = 6). Thiamin, riboflavin and PLP were stable on the DBS card during at least 15 days of room-temperature storage under vacuum in the dark, and the measurements of thiamin, riboflavin and PLP in the DBSs showed good agreement with the corresponding concentrations determined from liquid blood (R2 values >0.96). The validated method was successfully applied to the nutritional assessment of vitamins B1, B2, and B6 in 48 Chinese children.

Isotope dilution method for determination of vitamin B2 in human plasma using liquid chromatography-tandem mass spectrometry.

Vitamin B2 (riboflavin) is an essential constituent of the coenzymes flavin mononucleotide and flavin adenine dinucleotide and is critical for human metabolism and energy production. Liquid chromatography separation, then tandem mass spectrometry detection (LC-MS/MS) is a highly specific technique that enables quick analysis. An isotope dilution method for determination of riboflavin in human plasma using LC-MS/MS has been developed and validated in this study. In this method, 100 µL of plasma were added of 75 µL of an internal standard and treated with 125 µL of 0.1 M zinc sulfate. The analysis was performed using an Agilent 6460C tandem mass spectrometer system operated in the positive-ion mode. Chromatography separation performance was obtained with an Agilent 1290 UHPLC equipped with a Poroshell 120 SB-Aq column (100 mm × 2.1 mm × 2.7 µm) at a flow rate of 350 µL·min-1. Riboflavin was measured within an instrument run time of 2.5 min. Riboflavin content was found to follow a linear trend in the 0.5 to 50.0 ng·mL-1 range and dilution was validated for samples that exceed the last point of the calibration curve until two times. The intra-day relative standard deviation (RSD) was less than 10% and inter-day RSD was less than 11%. The average of recovery was 90.5-99.5%. A sensitive and selective method has been developed and validated successfully for quantitative analysis of riboflavin in human plasma with a simple sample extraction method and short execution time. The method is reliable and can be applied in clinical diagnosis of deficiency and supplementation monitored of this vitamin.

Applicability of AuNPs@N-GQDs nanocomposite in the modeling of the amplified electrochemical Ibuprofen aptasensing assay by monitoring of riboflavin.

Here, an ultrasensitive and low-cost electrochemical aptasensing assay is developed based on the applicability of a fabricated nanocomposite from nitrogen-doped graphene quantum dots (N-GQDs) and gold nanoparticles (AuNPs). A modified glassy carbon electrode (GCE) with the AuNPs@N-GQDs nanocomposite (AuNPs@N-GQDs/GCE) as an efficient platform has some unique properties such as high surface area and electrical conductivity. Furthermore, the prepared platform is capable of more loading of aptamer (Apt) molecules as a biological recognition element of Ibuprofen (IBP) on the modified electrode surface. It is noteworthy that in this study, riboflavin (RF) as a universal green probe is used for the first time for electrochemical detection of IBP. According to the proposed strategy and under the optimum condition, the unprecedented detection limit (LOD) of this assay (33.33 aM) is lower than previously reported analytical methods. The results demonstrate the ability of the nanocomposite for designing of the aptasensor, integrated within the electrode format, to cheaper and simpler detection of the IBP with a specificity and sensitivity sufficient for analysis in real samples. It seems that the proposed strategy based on the AuNPs@N-GQDs nanocomposite can be expanded to other nanomaterials. So, this is expected to have promising implications in the design of electrochemical sensors or biosensors for the detection of various targets.

Adequate vitamin B12 and riboflavin status from menus alone in residential care facilities in the Lower Mainland, British Columbia.

Older adults have potential increased risk of nutrient deficiencies because of age-related decreased dietary intake and malabsorption; it is important to ensure nutrient needs are met to avoid adverse health outcomes. B vitamins are of particular interest: vitamin B12 deficiency can cause irreversible neurodegeneration; there is mandatory folic acid fortification in Canada; and suboptimal riboflavin status has been reported among older adults in the United Kingdom. In this exploratory secondary analysis study we assessed vitamin B12 and riboflavin biochemical status (via microparticle enzyme immunoassay and erythrocyte glutathione reductase activity coefficient (EGRac), respectively), and the vitamin B12, riboflavin, and folate content of menus served to a convenience sample of older adults (≥65 years) from 5 residential care facilities within the Lower Mainland of British Columbia, Canada. Diet was assessed from customized 28-day cycle meal plans. Participants (n = 207; 53 men and 154 women) were aged 86 ± 7 years, largely of European descent (92%), and nonsmokers (95%). The menus served had a low prevalence of inadequacy for vitamin B12 and riboflavin (only 4% and 1% of menus contained less than the estimated average requirement (EAR), respectively), but 93% contained less than the EAR for folate. Mean ± SD serum total vitamin B12 concentration was 422 ± 209 pmol/L, and EGRac was 1.30 ± 0.19. The majority of older adults in residential care were provided with adequate vitamin B12 and riboflavin menu amounts, and only 5% were vitamin B12 deficient (<148 pmol/L). However, 26% were riboflavin deficient (EGRac ≥ 1.4), which may warrant further investigation.

Validation of the Brazilian Healthy Eating Index-Revised Using Biomarkers in Children and Adolescents.

The Brazilian Healthy Eating Index-Revised (BHEI-R) can be used to determine overall dietary patterns. We assessed the BHEI-R scores in children and adolescents, aged from 9 to 13 years old, and associated its component scores with biomarkers of health and dietary exposure. Three 24-h recalls were used to generate BHEI-R. Biomarkers were analyzed in plasma and red blood cells. Correlation tests, agreement, and covariance analyses were used to associate BHEI-R components with biomarkers. Data from 167 subjects were used. The strongest correlations were between fruits, vegetables and legumes with omega-6 and omega-3 fatty acids, and ß-carotene intakes. Milk and dairy correlated with plasma retinol and pyridoxine. All components rich in vegetable and animal protein sources correlated with plasma creatine. Total BHEI-R scores were positively associated with intakes of omega-6, omega-3, fiber and vitamin C, and inversely associated with energy and saturated fat intakes of individuals. Plasma ß-carotene and riboflavin biomarkers were positively associated with total BHEI-R. An inadequate food consumption pattern was captured by both biomarkers of health and dietary exposure. BHEI-R was validated for the above dietary components and can be associated with metabolomics and nutritional epidemiological data in future pediatric studies.

Severe riboflavin deficiency induces alterations in the hepatic proteome of starter Pekin ducks.

Suboptimal vitamin B2 status is encountered globally. Riboflavin deficiency depresses growth and results in a fatty liver. The underlying mechanisms remain to be established and an overview of molecular alterations is lacking. We investigated hepatic proteome changes induced by riboflavin deficiency to explain its effects on growth and hepatic lipid metabolism. In all, 360 1-d-old Pekin ducks were divided into three groups of 120 birds each, with twelve replicates and ten birds per replicate. For 21 d, the ducks were fed ad libitum a control diet (CAL), a riboflavin-deficient diet (RD) or were pair-fed with the control diet to the mean daily intake of the RD group (CPF). When comparing RD with CAL and CPF, growth depression, liver enlargement, liver lipid accumulation and enhanced liver SFA (C6 : 0, C12 : 0, C16 : 0, C18 : 0) were observed. In RD, thirty-two proteins were enhanced and thirty-one diminished (>1·5-fold) compared with CAL and CPF. Selected proteins were confirmed by Western blotting. The diminished proteins are mainly involved in fatty acid ß-oxidation and the mitochondrial electron transport chain (ETC), whereas the enhanced proteins are mainly involved in TAG and cholesterol biosynthesis. RD causes liver lipid accumulation and growth depression probably by impairing fatty acid ß-oxidation and ETC. These findings contribute to our understanding of the mechanisms of liver lipid metabolic disorders due to RD.